Proverbs 4

1 The Hebrew word for instruction here clearly connotes discipline. If a child responds properly to good teaching and proper correction he will gain the ability to handle any problem he has during life.
2 The father assures the sons that he is teaching them what is right, and he exhorts them not to turn away from good teaching.
3 Solomon's education started even before his mother had more children (Solomon had older half-brothers, but he was the firstborn of his mother). King David taught Solomon what was right and admonished him to hold fast to good teaching. We do not hear of King David having these kinds of conversations with his other sons. It appears he was too busy fighting battles or managing the kingdom to raise his sons properly. After being grieved on many occasions David must have decided that Solomon was his last chance to raise a son well.
4 The heart here refers to the will, or the "real you." It is not just obedience, but what is being obeyed that can give life. Since the father's teaching encourages obedience to God, keeping these commandments leads to eternal life.